List of top Questions asked in KEAM- 2025

The Vividh Bharati station of All India Radio, Kozhikode, broadcasts on a frequency of \( 1500\,\text{kHz} \). What is the wavelength of the electromagnetic radiation emitted by the transmitter? \( (c = 3\times10^8\,\text{m s}^{-1}) \)

Which of the following pair of oxides is neutral?

The reverse biasing in a junction diode,

The correct increasing order of dipole moment of \( NF_3, H_2S, CHCl_3 \) and \( NH_3 \) is

The density of \( 3\,M \) aqueous solution of a solute \( X \) is \( 1.86\,\text{g mL}^{-1} \). The molality of the solution is (Molar mass of solute \( X \) is \( 120\,\text{g mol}^{-1} \))

Which of the following experimental phenomenon is explained by the wave nature of electromagnetic radiation?

An alternating voltage of \( 250\,\text{V},\,50\,\text{Hz} \) is applied to a full wave rectifier. If the internal resistance of each diode is \( 10\,\Omega \) and the load resistance is \( 5\,\text{k}\Omega \), the peak value of output current is

In Young's double slit experiment, the band width of the fringes observed is \( \beta \), when light of wavelength \( \lambda \) is used. With same experimental set up, to double the band width of the fringes, the wavelength of light required is

If \( \lambda \) be the wavelength of any electromagnetic radiation, the de-Broglie wavelength of its quantum (photon) is

The greatest wavelength of the radiation that will ionize unexcited hydrogen atom is

Pick out the INCORRECT statement from the following:

The half-life periods of two radioactive materials A and B are 1500 years and 1200 years respectively. If their mean life periods are \( \tau_A \) and \( \tau_B \) respectively, then the value of the ratio \( \frac{\tau_A}{\tau_B} \) is

The self-inductance of an air core solenoid is \( L \). If the number of turns in the solenoid is doubled, keeping all other factors constant, then its self-inductance will be

An alternating current having the peak value \( 10\sqrt{2}\,\text{A} \) is used to heat a metal wire. To produce the same heating effect, the constant current required is

If \( v_g, v_X \) and \( v_v \) are the speeds of gamma rays, X-rays and visible light respectively in vacuum, then

The Brewster's angle \( i_B \) for any interface should lie between

When a ray of light moves from one medium to another medium,

If a magnetic material has magnetic susceptibility \( \chi = -0.5 \), then its relative magnetic permeability \( \mu_r \), and the type of material is

In a cyclotron, if the frequency of the accelerating field is doubled, then the radius of the charged particle moving in a circular path will be

If an equilateral triangle is made of a uniform wire of resistance \( R \), then the equivalent resistance between the ends of a side is

A galvanometer of resistance \( 100\Omega \) gives a full scale deflection for a current of \( 1\,\text{mA} \). The resistance required to convert it into a voltmeter which can read up to \( 2\,\text{V} \) is

The dependence of drift velocity \( v_d \) on the electric field \( E \), for which Ohm's law is obeyed is

When \( n \) identical cells are connected in parallel,

A given charge \( Q \) is divided into two parts which are then kept at a distance \( d \) apart. The electrostatic force between them will be maximum if the two parts are

A string of length \( l \) is divided into three segments of lengths \( l_1, l_2 \) and \( l_3 \) with the fundamental frequencies \( n_1, n_2 \) and \( n_3 \) respectively. The original fundamental frequency of the string is given by